servers/ipc/main.c

   1 #include "inc.h"
   2
   3 int identifier = 0x1234;
   4 endpoint_t who_e;
   5 int call_type;
   6 endpoint_t SELF_E;
   7
   8 static struct {
   9         int type;
  10         int (*func)(message *);
  11         int reply;      /* whether the reply action is passed through */
  12 } ipc_calls[] = {
  13         { IPC_SHMGET,   do_shmget,      0 },
  14         { IPC_SHMAT,    do_shmat,       0 },
  15         { IPC_SHMDT,    do_shmdt,       0 },
  16         { IPC_SHMCTL,   do_shmctl,      0 },
  17         { IPC_SEMGET,   do_semget,      0 },
  18         { IPC_SEMCTL,   do_semctl,      0 },
  19         { IPC_SEMOP,    do_semop,       1 },
  20 };
  21
  22 #define SIZE(a) (sizeof(a)/sizeof(a[0]))
  23
  24 static int verbose = 0;
  25
  26 /* SEF functions and variables. */
  27 static void sef_local_startup(void);
  28 static int sef_cb_init_fresh(int type, sef_init_info_t *info);
  29 static void sef_cb_signal_handler(int signo);
  30
  31 int main(int argc, char *argv[])
  32 {
  33         message m;
  34
  35         /* SEF local startup. */
  36         env_setargs(argc, argv);
  37         sef_local_startup();
  38
  39         while (TRUE) {
  40                 int r;
  41                 int ipc_number;
  42
  43                 if ((r = sef_receive(ANY, &m)) != OK)
  44                         printf("sef_receive failed %d.\n", r);
  45                 who_e = m.m_source;
  46                 call_type = m.m_type;
  47
  48                 if(verbose)
  49                         printf("IPC: get %d from %d\n", call_type, who_e);
  50
  51                 if (call_type & NOTIFY_MESSAGE) {
  52                         switch (who_e) {
  53                         case VM_PROC_NR:
  54                                 /* currently, only semaphore needs such information. */
  55                                 sem_process_vm_notify();
  56                                 break;
  57                         default:
  58                                 printf("IPC: ignoring notify() from %d\n",
  59                                         who_e);
  60                                 break;
  61                         }
  62                         continue;
  63                 }
  64
  65                 /*
  66                  * The ipc number in the table can be obtained
  67                  * with a simple equation because the values of
  68                  * IPC system calls are consecutive and begin
  69                  * at ( IPC_BASE + 1 )
  70                  */
  71
  72                 ipc_number = call_type - (IPC_BASE + 1);
  73
  74                 /* dispatch message */
  75                 if (ipc_number >= 0 && ipc_number < SIZE(ipc_calls)) {
  76                         int result;
  77
  78                         if (ipc_calls[ipc_number].type != call_type)
  79                                 panic("IPC: call table order mismatch");
  80
  81                         /* If any process does an IPC call,
  82                          * we have to know about it exiting.
  83                          * Tell VM to watch it for us.
  84                          */
  85                         if(vm_watch_exit(m.m_source) != OK) {
  86                                 printf("IPC: watch failed on %d\n", m.m_source);
  87                         }
  88
  89                         result = ipc_calls[ipc_number].func(&m);
  90
  91                         /*
  92                          * The handler of the IPC call did not
  93                          * post a reply.
  94                          */
  95                         if (!ipc_calls[ipc_number].reply) {
  96
  97                                 m.m_type = result;
  98
  99                                 if(verbose && result != OK)
 100                                         printf("IPC: error for %d: %d\n",
 101                                                 call_type, result);
 102
 103                                 if ((r = sendnb(who_e, &m)) != OK)
 104                                         printf("IPC send error %d.\n", r);
 105                         }
 106                 } else {
 107                         /* warn and then ignore */
 108                         printf("IPC unknown call type: %d from %d.\n",
 109                                 call_type, who_e);
 110                 }
 111                 update_refcount_and_destroy();
 112         }
 113
 114         /* no way to get here */
 115         return -1;
 116 }
 117
 118 /*===========================================================================*
 119  *                             sef_local_startup                             *
 120  *===========================================================================*/
 121 static void sef_local_startup()
 122 {
 123   /* Register init callbacks. */
 124   sef_setcb_init_fresh(sef_cb_init_fresh);
 125   sef_setcb_init_restart(sef_cb_init_fresh);
 126
 127   /* No live update support for now. */
 128
 129   /* Register signal callbacks. */
 130   sef_setcb_signal_handler(sef_cb_signal_handler);
 131
 132   /* Let SEF perform startup. */
 133   sef_startup();
 134 }
 135
 136 /*===========================================================================*
 137  *                          sef_cb_init_fresh                                *
 138  *===========================================================================*/
 139 static int sef_cb_init_fresh(int UNUSED(type), sef_init_info_t *UNUSED(info))
 140 {
 141 /* Initialize the ipc server. */
 142
 143   SELF_E = getprocnr();
 144
 145   if(verbose)
 146       printf("IPC: self: %d\n", SELF_E);
 147
 148   return(OK);
 149 }
 150
 151 /*===========================================================================*
 152  *                          sef_cb_signal_handler                            *
 153  *===========================================================================*/
 154 static void sef_cb_signal_handler(int signo)
 155 {
 156   /* Only check for termination signal, ignore anything else. */
 157   if (signo != SIGTERM) return;
 158
 159   /* Checkout if there are still IPC keys. Inform the user in that case. */
 160   if (!is_sem_nil() || !is_shm_nil())
 161       printf("IPC: exit with un-clean states.\n");
 162 }
 163